In a system for stimulation of nerves comprising implanted electrodes, an external to the system trigger device is equipped with a sensor and a transmitter for wirelessly broadcasting a signal to be received by a pulse generator for generating a pulse pattern to be forwarded to the at least one electrode implanted in the corpus of the living being. Further the trigger device is equipped with means for detecting if the patient is walking or just standing pulling the weight from one leg to another and can thus determine if a stimulation sequence has to be performed.
